I. Field of the Invention
The present invention relates generally to carburetors and, more particularly, to a carburetor with pressure and temperature compensating means.
II. Description of the Prior Art
There are a plurality of previously known carburetors and many of these carburetors employ a housing with a fuel or float bowl into which fuel is supplied by a fuel pump. A float is mounted within the float bowl and is operatively connected with a fuel shut-off valve so that the float permits the fuel valve to open only when the fuel in the float bowl falls below a predetermined level. In this fashion, the float maintains the fuel at a predetermined and constant level within the float bowl. Moreover, the fuel level in the float bowl determines the amount of fuel supplied to the engine via the carburetor venturi, idle and transfer ports.
It has been the conventional practice with these previously known carburetors to preset the float to maintain a fuel level designed to supply the desired amount of fuel to the venturi at a barometric pressure of 29.92 inches of mercury and a temperature of 60.degree. F. Consequently, at this air pressure and temperature, the previously known carburetors generate or create the proper fuel/air ratio for the most efficient operation of the engine. Conversely, when the pressure and temperature vary from these standards, the fuel/air ratio of the combustible mixture produced by the carburetor also varies and produces either overly rich or overly lean fuel/air mixtures. These deviations from the ideal operating conditions in turn result in increased exhaust pollutants and reduced gas mileage for the engine utilizing the carburetor.
There have been several previously known carburetors which employ altitude compensation means for regulating the fuel/air mixture with the barometric pressure changes. However, no previously known carburetor has been heretofore known for controlling the fuel/air ratio proportionately with both the barometric pressure and temperature, and hence density, of the incoming air to the carburetor.